GB2481428A - Passive emanation device - Google Patents

Abstract

A passive emanation device 1 emanates a volatile liquid 5 containing one or more active materials, wherein the active material comprises at least one of: a fragrance, insecticide, fungicide, pesticide, sanitising material and/or pharmaceutical. The passive emanation device comprises a housing 2, a volatile liquid reservoir 4, one or more capillary tubes 7 in non-valved fluid communication with the reservoir at one end thereof, a nozzle 8 located at the end of each capillary tube(s) remote from the reservoir wherein each nozzle is in non-valved fluid communication with each capillary tube(s); and an emanation substrate 6, wherein the housing is arranged to support the reservoir, capillary tube(s) and nozzle in spatial arrangement over the emanation substrate. The emanation substrate can be made from any natural or synthetic material that is capable of at least partially absorbing the volatile liquid. A method of providing a flow rate of volatile liquid between 0.1-500 mL/hr onto the emanation substrate is also claimed.

Description

ile:LicEflDevice

Field of the Invention

The present invention relates to a volatile liquid emanation device wherein said volatile liquids comprise active components such as fragrances, insecticides, fungicides, pesticides, sanitizing materials and pharmaceuticals are provided, and particularly the present invention relates to a passive, non-powered volatile liquid emanation device.

Backoround Conventional passive emanation devices for volatile liquids typically work by exposing a one side of a penneable membrane to a reservoir of the volatile liquid. In such membrane-containing emanation devices, the membrane is in constant contact on one aide thereof with the liquid and exposed to the external environment on its other sideS. The contact between the volatile liquid and membrane causes the membrane to uptake the liquid by capillary action and/or diffusion, thus permitting the emanation of the liquid by evaporation from its surface eçosed to the environment. Whilst such devices are simple to construct they contain several drawbacks, some r of which are identified below. r

One drawback, particularly with the emanation of air fresheners is that of a phenomenon called o aabituation Habituation s when users of a continuously emanating air freshenei qet so used to the fragrance of the air freshener that they become unable to notice it after a period of time. This i's problematic in particular with non-automated air freshening devices where the user is given no visual clues as to whether the device is emanating a fragrance or not.

A furthci diawbacK associated tn devoec having a membrane in constant uontact with a volatile material such as a volatile liquid air fiesheno s the pnenomeia of vacuum build up The vacuum build-up phenomena can occur inside the housing due to the wetted membrane being unable to allow sufficient flow of air therethrough in order to equatise the drop in pressure inside the housing caused bythe emanation of the volatile material. This build-up phenomena can cause unacceptable performnanc'e problems with such a device from a consumer perspective.

In the held of air freshening it e generally preferred to use a volatile liquid fragrance/air freshener comprising several components. These components often possess different volatilities which can lead to emission problems. In devices having a membrane in constant contact with the volatile liquid, an accumulation of volatile liquid components with the lowest volatilities can occur leading to an undesirable non-uniform emanation profile for the liquid.

In either or both cases of build-up phenomena and accumulation of low volatility components, the evaporation rate, and thus the emanation rate, of the volatile Uquid adopts the profile shown in Fig. 4.

Eventually the emanation rate may reach equilibrium (dashed line) where the rate of evaporation of each individual component of the volatile liquid away from the membrane surface is equivalent to the rate of deposition due to diffusion and the device cannot maintain any further vacuum.

A further drawback with known passve volatile liquid emanators is that prulingen exrosuie of the volaulo hqutd o a wicking material such as a memmane or the like can cause fractionation ovu time due to various factors such as the wicking material having a limited porosity affecting liquid transfer rates/evaporation rates vinich, in turn: can change the character and/or intensity of the volatile liquid being emanated. Changes in character of emanated volatile liquids is particularly noticeable for fragrances wherein common wicking materials cause the high notes' of a fragrance to be evaporated when the wicking material is first exposed to the fragranced liquid, and the low notes' ans evaporated thereafter which affects the user's experience. r

r Accordingly, it is an object of the present invention to provide a device that is capable of addressing the abovementioned performance drawbacks and other drawbacks that will be o appreciated by a person skitled in the art.

Summary nf Invention

According to a first aspect of the present invention there is provided therefore a passive emanation device for emanating a volatile liquid conthining one or more active materials wherein rh actrve niterialcumpnses at tuast one of afragianLe an insecticide a fungicide d pesticide a sanitising material; and/or a pharmaceutical; and wherein the passive emanation device comprises: a housing; a volatile liquid reservoir; one or more capillary tubes in fluid communication with the reservoir at one end thereof wherein said one or more capillary tubes are in non-valved fluid communication with the reservoir; a nozzle located at the end of the or each capillary tube(s) remote from the reservoir wherein the or each nozzle is in non-valved fluid communication with the oreach capillary tube(s); and an emanation substrate; wherein the housing is arranged to support the reservoir, capillary tube(s) and nozzle(s) i.n spatial arrangement over the emanation substrate.

In the context of the present invention "non-valved" should be understood as meaning that that component of the device has no mechanical features which enable it tu regulate or adjust the flow of liquid therethrough.

In the context of the present invention passive" should he understood as meaning that that the device is operable without a power source or sonic other means which drives the emanation of the volatile liquid; in other words the device of the present invention only requires gravity in order emanate volatile liquid.

According to a second aspect of the present invention there is provided therefore a passive emanation device comprising: a housing; a volatile liquid reservoir holding a volatile liquid containing one or more active materials wherein the active material comprises at least one of: a fragrance; an insecticide; a fungicide; a pesticide; a sanitising material; and/or a pharmaceutical; one or more capillary tubes in fluid commun cation with the rese voir at onc eno tnei eof Mierein r said one or morc capillary ubes aie in non-valved fluir4 comminicarion with the reservoir r a nozzle located atthe end of the or each capillary tube(s) remnotefrom the reservoir wherein the or each nozzle is in non-valved fluid communication with the or each capillary tube(s); and o an emanation substrate; wherein the housing is arranged to support the reservoir, capittary tube and nozzle in spatial arrangement over the emanation substrate.

According to a *third aspect of the present invention there is provided therefore a delivery mechanism for a passive emanation device according to the first aspect of the present invention, wherein the delivery mechanism is connectable, preferably reieaseably connectable, to a housing of the passive emanation device and wherein he delivery mechanism comprises a volatile liquid reservoir hotding a volatile tiquid containing one or niore active materials wherein the active material comprises at least one of: a fragrance; an insecticide; a fungicide; a pesticide; a sanitising material; and/or a pharmaceutical; one or more capillary tubes in fluid communication with the reservoir at one end thereof wherein said one or more capillary tubes are in non-valved fluid communication with the reservoir; a nozzle located tthe end of the or each capillary tube(st nmote fiori the reservou wherein the oreach nozzle m in non valved fluid Lomflunaton with the or each ceoiIlaretnbe, According to a forth aspect of the present inventiOn there is provided a method of providing a normal flow rate of volafle liquid between substantially 01 -500pLThr on to an emanation substrate. wherein the method comprises the steps of piecing a device according to the second aspect of the present invention in a location where emanation of the volatile liquid is desired and causing the normal flow of liquid from the device toward the emanation substrate.

The non vafted arrangement may provicie a deacs that once the hquid is allowed to flow rom the reservoir the liquid will flow substantially confinuously from the reservoir into the capillary tube to the nozzle and on to the emanation substrate at a noniial flow rate of between substantially 0.1 - 500pLThr. and preferably between substantially 1 SOpL/hr. This normal flow rate has, surprisingly, been found to represent the optimal.rate to emanate the volatile liquid to ensure satisfactory emanation thereof whilst minimising the onset of habituation to the volatile liquid. The mass oeach drop'el is preferably between substantially 0 500mg coo more piefeiably between substantially 0.5 70mg.

The intenrelaflonship of the various components of the deviceIdelivery mechanism is critical in ensuring that the desired normal flow rate and droplet size is achieved.

r The reservoir is preferably substantially completely enclosed to prevent the evaporation of volatile r liquid theiefrom The reservoir is preferably povided w'th a vent hole that can be opened to permit the flow of volatile liquid from the reservoir without the build up of negative pressure or a o vacuum in the headspace of the reservoir. The vent hole is preferably provided in a side wall or an upper cover of the reservoir above tne max neight of the vola tile tiouid retained therein to permh air to vent into the headspaceof the reservoir above the volatile liquid. The vent hole is preferably provided with an area of between substantially 7.9x10 -l.OxlO3nini2, and even more preferably with an area of between suhsntially 0.8 -. 3.1mm2. The vent hole is preferably substantially cylindrical and provided with a diameter of between substantially 001 -50mm, and even more preferably with a diameter of between substentiafly I.. 2mm.

I ne vent nole may be coveten by a removable seal meinbei such that once opened it snall iemain open Alternmely The vent hole may be coveied by a re-sealable sealino niembei which can be opened and resealed as desired by the user to, in effect, turn the emanation ot volatile liquid from the device between a binary on and off position but without providing a user with the ability to select a position therebetween which could alter the normal flow rate.

The iesmvuir may be sized to retain a olunie f volatile liquid between substantialli 0 t -flOOml and preferably between substantially 10 4Oml, The reservoir may be shaped such that the volatile liquid head height therewithiri is between substantially 0.1 100cm, and preferably between substantiafly 3 10cm; the liquid head height is defned within the context of the present invention as heng the hthrjhtof the quid from the nozzle to the fiquid-air surlhce in the reservoir.

The device/delivery mechanism may be provided with a mechanical boost means which is operable to increase the flow rate of the volatile liquid from the normal flow rate to an enhanced flow rate.

Preferably the mechanical boost means is in the form of an air pump connected to the reservoir which allows a user to pump air into tho headspace of the reservoir to increase the air pressure thereof to atleast temporarily increase the flow rate from the normal flow rate to the enhanced flow rate, once the user ceases further pumping the normal flow rate will resume once the air pressure in the head space equalises over a period of time.

Alternatively an auxiliary flow route for the volatile liquid may he provided: said auxiliary flow route r being operable to being opened by a user to increase the flow rate to the enhanced flow rate r before being closed and the flow rate being retumed to the normal flow rate. The auxiliary flow route may be provided in the form of an aperture in the reservoir, possibly connected to a conduit o wherein the flow of volatile liquid therethrough is controlled by a valve that can be manipulated by a user The auxlrary flow route would preferably oe pro ded rth a liqurd exit onfice located substantially above, the emanation substrate.

The auxiliary flow route may be connected to a auxiliary reservoir of volatile liquid which is adjacent to but not in liquid coi-nmunication with the reservoir.

The enhanced flow rate may be between substantially 2 -50 times greater than the normal flow rate, and preferably between substantially 2 5 times greater than the normal flow rate.

The reservoir may ha provided in any shape, however: a substantially cylindrical shape is preferred. For substantially cylindrically shaped reservoirs they may be provided with a diameter of between substantially 1 -50cm. but preferably with a diameter of between substantially 4 -Scm, and may be provided with a depth of between substantially 0.1 100cm, hut preferably with a depth of between substantially 0.5 -2cm.

Preferably at least a portion of the reservoir is transparent to penmit a user to see the level of volatile liquid held within, preferably substantially all of the reservoir is transparent.

Preferably the devices/delivery mechanisms according to the present invention are provided with a single capdlary connetthd to the iescivos The or each capHlary tube is preferably made of glass or plashc and may be substantially cylindrical although it could he provided in numerous other geometric shapes. The capillary tube(s) is preferably of a uniform shape and crosssection throughout its length. The capillary tube(s) maybe providedwith a length of between substantiallyO.1 -5Qcm,and preferablywith a length or between substantiall, 3 10cm In the most prererred embodiment the capillary ubet is/are substantially cylindrical and provided with an internal diameter of between substantially I 1000pm, and preferably with an internal diameter of between substantially 75 100pm.

The capillary tube(s) may be provided with a filter to ensure that any contaminants in the volatile liquid do not inadvertently cause a blockage to liquid entering and moving along the capillary during use. thus, potentially affecting the flow rate r The nozzle(s) is/are preferably provided with a substanally circular exit orifice having a diameter r of between substantially 0.01 -100mm, but preferably has a diameter of between substantially 0.4-2mm. The nozzle(s) may be provided with a cap to ensure that no volatile Ii uld is lost o therenorn puor to se by a user The volatile liquid for use with the device/delivery mechanism of the present invention preferably possesses the at least one of, or more preferably two of, or most preferably al three of the following properties: -viscosity between substantially 0.1 -1 OOcP, and preferably between substantially I -5cP; -oensty between substanially0 1 -lOg/L and pieferabl. between subsiaritiallvO 8-1 lg/L aveiago 5t i ace tonsion between subttannally 1 -lOOrnNim snd pre'erably hetween substantially 1 -5am N/rn.

The emanation substrate maybe made of any suitable material that may capture the volatile liquid Omplet, preferably the emanation substrate is made from a material that is capable of at least partially absorbing the volatile liquid.

The housing is preferably provided in the form of an open framework which is configured to suspend the reservoir such that the capillary and nozzle are held direcilyabove a substantially central point of the emanation substrate. Whilst an open framework is preferred since a user villl be able to monitor the progress of volatile liquid from the reservoir through the capillary tube and out of the nozzle on to the emanation substrate, the framework may he totafly or partially enclosed to improve the safe operation of the device by preventing a user from being able to nterrupt the fiow from the liquio fiom the nozzle to the entanation substrate The preferred volathe liquid used with the device/delivery rnechanism/niethod of the present invention is fragranced liquid for use as an air freshener. The present invention has been found to be particularly advantageous compared with known emanation methods due to the nature of fragranced volatile liquids.

Bnef Description of the jins

Embodiments of the invention will now be described, by way of example only, with reference to the following drawings in whictu Fig 1 illustrates a side secuonec view of en emanation de iice Fig. 2 illustrates a perspective view of the emanation device; and Fig. 3 iliustratesa perspective view of a delivery mechanism for a passive emanation device.: r yjgfion of an Embodiment r Figs. 1 & 2 illustrate an passive emanation device I which is generally arranged to have a housing 2 provided in the form of framework 3 supporting a reservoir 4 which contains a quantity o of vo atile liquidS The reseroir4 is suppoited osercn crnnnttioii substrate o The tesorvoii ib provided with a capillary tuoe 7 which exter ds from a substantially cntral porbou ol the reseivoii 4 toward the emanation substrate 6. At the remote end of the capillary tube 7 is located a nozzle S from which, in use, volatile liquid will drop towards tte emanation substrate 6.

Specifically the device 1 is a passrve emanator as it is not powered by any form of propuleon or motor oi dcc'-icitv etc iatnr it simply relies on ihe force of giasitv to be operable and piovid a normal flow rate. The device I is, importantly, non-valved in that then are no mechanical features of the detivery mechanism which can be altered to reduce the normal ftow rate of liquid from the reservoir 4 to the emanation substrate 6 once the liquid has been allowed to flow, thus ensuring that the device is operating at an optimum flow rate or not operating at all. The optimum flow rate (the normal flow rate) for this device is 0.1 -500pL/hr. but preferably the rate is between substantially 1 -5OpLThr. This optimum flow rate is, ideally, achieved whilst maintaining the mass of each droplet at between substantially 0.1 -500mg, and but preferably between substantially 0.5 -70mg. Clearly the inter-relationship of the varous components of the device I is critical in ensuring that this optimum flow i-ate and droplet mass is achieved.

As showm in Figs. 1 & 2 the reservoir 4 is substantially completely enclosed which acts to prevent evaporation of volatile liquid 5 therefrom. The reservoir 4 has a vent hole 0 that can be opened to permit the f'ow of volatils liciuid 5 horn the roser air 4 witnouttne build up of negative piessure or a vacuum in the headspace of the reservoir. The vent hole 9 is provided in the upper cover of the reservoir. The vent hole 9 is covered by a re-sealable sealing member 10 which operates via a screw thread mechanism to allow it to he brought into and out of sealing engagement with a upper surface of the vent hole 9.

The reservoir 4 may be sized to retain a volume of volatile liquid between substantially 0.1 -SOOml, but in Figs. 1 & 2 it is sized to retain between substantially 10 -4Oml, The volatile liquid head heig.ht therewith in may be between substantially 0.1 -100cm. but is shown as being between substantially 5-12cm.

The reservoir 4 may be provided in any shape, however, Figs. I &2 show the reservoir 4 to he substantially cylindrical with a diameter of between substantially 4 -8cm and a depth of between substantially 0.5 -2cm. r

r The framewoik 3 is of an open configuration so that it does not obscure the reservoir 4 which is transparent, thus permitting a user to see the level of volatile liquid held within. The capillary tube o 7 is also tiansparc it which allows the user to monitor the progress of voud threthiough on its journey toward the emanation substrate 5.

The capillary tube 7 is shown as being made of glass and hang a substantially uniform cylindrical shape having an internal diameter of between substantially 7S-100pm and a length between substantially 3 10cm. The capillary tube 7 ends at its lowermost portion with the nozle P whch is shown as having an exit cnfic betwoon si. bsthntiailv 0 4-zmni Tne nozile is shown as being suiioundeo by a capillary housinq 1 which provides additional safet foi the operation of the device but ensuring that the potentially delicate capillary tube 7 and nozzle 8 can not be accidentally interfered with by a user during normal operation. Furthermore, the capillary housing 11 offers the nozzle 8 a degree of shielding from air currents surrounding which may affect the flow rate of votafile liquid droplets leaving the nozzle. Although not shown, the capillary housing 11 and/or the nozzle 8 may be provided with a cap to ensure that no volatile liquid is lost therefrom prior to use by a user.

The emanation substrate S could be made from any natural or synthetic material that is at least partially absorbent but is shown here as being made from a natural material which isat least partially absorbent so that it can emanate the volatile liquid over a prolonged period and, also, C-> C> ensure that the Liquid dropped thereon does not remain in drop form resistant to evaporation dim to the surface ten zion thereof.

Fig 3 shos a dehvery mernnivrn 11 which cur sisrs of a reset vcir 4 vninh hold a quantity of volatile liquid 5 covered by a cap of the like (not shown), the reservoir 4 having a capillary tube 7 terminating in a nozzleS. The delivery mechanism 12 could be used as a n3fill wherein it is replaceable within the housing 2 once the reservoir 4 held therewithin has been exhausted.

Examdles are now doscubed which Unsuate the interoperation of the aious parameters required to produLe a 1eice havino the opu um tlow rates called foi n the devises of the present invention.

Example I

Capillary Length 46 mm Inner Capillary Diameter lOG pm __________ Nozzle Diameter I A mm _______ r Drop weight _______________ r Reservoir Volume 30 mL

-___ -

Liquid Head Height (from 56.6 mm O noz4e Up to top of liquid) ___________ Rose rvou Diametei' 6 cm Reservoir Depth 1.06 cm flncer _________ ______________ (\J Vent Hole Diameter 1 mm Fragrance Viscosity 32 oP _____ -Fragrance Density -O.89q/L ffgrance Surface Tension 26mN!m Flow Rate 29.7 uL/hr

Example 2

Capillary Length 100 miii Inner Capillary Diameter 100 pm Nozzle Diameter 5.9 mm __________ Prc weight 29mg Reservoir Volume 30 mnL fp9n3nce} _________ Lquio Heau Height (from 110 6 mm no2zletDpjiurj _______________ Reservoir Diameter 6 cm Reservoir Depth 1 Gb cm

_____________

Vent Hole Diametor I mm Fragnco cosit 32 oP -FrewanceDencty 0 89giL ____ Fragrance Surfsre Tension ?Q mN/rn Flow Rate 26.7 uL/hr Both devices from examples 1 & 2 were opemted fbr a continuous period unti the fragranced volatile liquid was exhausted and both devices consistently produced the flow rates and drop weights described above.

All of the features disclosed in this specification tincluding any accompanying claims, abstract and diawinqs) and/rn cdl of the steps of any metnod or process so disclosed maybe combineo in any combinafion, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternave features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus; unless expressly stated otherwise; each r feature disclosed is one example only of a genenc senes of equivalent or simnar reatures, r The invention in not restricted to the details of the foregoing embodiment(s). The invention 0 extends ro any novel one or any novel combination of the features disc osed in this specification c\i (induding any accompanying dauns abstrart and drawingsi or TO any novel one or any noval combination, of the steps of any method or process so disdosed.

Claims (1)

1. Claims 1. A passive emanation device for emanating a volatile liquid containing one or more active materials wherein the active material comprises at least one of a fragrance; an insecticide; a fungicide a pesticide a 3dnitising material and/or a pha maceutical md wherein tie passive en anation device cempnses a housing; a volatile liquid reservoir: one or more capillary tubes in fluid communication with the reservoir atone end thereof wherein said one or more capillary tubes are in ndmvalved fluid communication with the reservoir; a nozzle located at the end of the or edch capillary tubets) remote from the reservoir vnierein the orezch nozzle i' in non valveo fluid communication with the oreah capilla3ywbe(s) ano an emanation substrate; wherein the housing is arranged to support the reservoir, capillary tube(s) and nozzle(s) in spatial arrangement over the emanation substrate.

   2. .A device according to claim I, wherein the device is configured to afiow liquid on to the emanation substrate at a normal flow rate of between substantially 0 hOOpLA ir and pi cierably between substantially I 50pL/hr.

   3. A device according to claim I or claim 2, wherein the device is configured to allow the mass of each liquid droplet to be between substantially 0.1 -500mg, and preferably between subsiantially 0.5 -70mg.

   4. A device according to any precading claim, wherein the reservoir is provided with a vent hole.

   5. A device according to claim 4, wherein thevent hole is covered by a re-sealable sealing memberwhich can be opened and re-sealed.

   6. A device according toany preceding claim, wherein the reservoir is sized to retain a volume of volatile liquid between substantialiyO,I -500m1, and preferably between substantially -4Oml.

   7. A device accordngto any preceding claim, wherein the reservoir is shaped such that the volatile liquid head height therewithin is between substantially 0.1 -100cm. and preferably between substantiaily 3-10cm. Ii

   5. A device according to any preceding claim, wherein the reseir is substantially rylindrically chapeo nd ha\e a diameiei of between substantially -50cm but preferabi i between suostanvally4--8cm and haiea depth of between subatentiallyo 1 100Gm but preferably between substantially 0.5-2cm.

   9. A device according to any preceding clafrn, wherein a single capillary tube is provided.deuce nccording to an prcceding claim wherein the capillary tube(si is/are provcled with a length of between substantially 0 1 -50cm and preferably with a length of between substanbally3-ltcm.11. A device according to any preceding claim, wherein the capillary tube(s) is/are substantially cjhndncal and provided with an nreinai diameter of Letween substantially I -to0pni and preferably with sn internal drarnetorofoetwen substantially 75 100pm 12. A device according to any preceding claim, wherein the nozzle(s) is/are provided with a substantially circular exit orifice having a diameter of between substantially 001 -100mm, but preferably has a diameter of between substantially 0.4 -2mm, 13. A device according to any preceding claim, wherein the emanation substrate. is made riom a niterial that is capable of at least partially absorbing the voiatils liquid 14. A device according to any preceding claim, wherein the housing is provided in the form of an open framework which is configured to suspend the reservoir such that the capillary and nozzle are held directly above a substantially central point of the emanation substrate.A delivery mzchanism for a passive emanation de ice accor oing to any precciing claim wheioin the delivery mechanism is con leciable preferabl ieleaseablj connectaole to a housino of the passive emanation device arid wherein the delivery mechanism comprises: a volatile liquid reservoir holding a volatile liquid containing one or niore active materials wherein the active material comprises at least one of: a fragrance; an insecticide; a fungicide: a pesticide: a sanitising material; and/or a pharmaceutical; one or more capillary tubes in fluid communication with the reservoir at one end thereof wherein said one or more capillary tubes aie in non-valved fluid communication with the reser von a nozzle located at the end of the or each capillary tube(s) remote from the reservoir wherein the or each nozzle is in non-valved fluid communication with the or each capillary tube(s).16. A passive emanation device comprising: a housing; a volatile liquid reservoir holding a volatile liquid conining one or more active materials wherein the active material comprises at least one of: a fragrance; an insecticide; a fungicide; a pesticide; a sanitising material; and/or a pharmaceutical; one oi mote capi'larv tubes in fluid communication with the reservoir atone end hereof wherein said one or more capillary tubes are in non-valved fluid communication with the reservoir; a nozzle located at the end of the or each capillary tube(s) remote from the reservoir wherein the or each nozzle is in non-valved fluid communication with the or each capillary tube(s); and an emanation substrate; wherein the housing is arranged to support the reservoir, capillary tube and nozzle in spatial anangement over the emanation substrate.17. A mechanism or device according to either claim 15 or claim 16 respectively, wherein the volatile liquid possesses the at least one of, or more preferably two of, or most preferably all three of the following properties: -viscosity between substantially 0.1 -l0OcP, and preferably between substantially 1 -5cP; density betwc,,n suostantially 0 1 -lOq/L and prefnrsbly between substantially 08-1 lq/L -average surface tension between subsntiaily 1 -100mN/m, and prefembly between substantially I -5OmN/rn.18. A method of providing a flow rate of volatile liquid between substantially 0.1 -500,uL/hr on to an emanation substrate, wherein the method comprises the steps of placing a device according to claim 16 in a location where emanation of the volatile liquid is desired and causing the flow of liquid from the device toward the emanation substrate.19. A passive emanation device substantially as described herein and with reference to the drawings. In I 3*::r: INTELLECTUAL . ... PROPERTY OFFICE Application No: GB 1010594.8 Examiner: Mr Alun Owen Claims searched: 1-19 Date of search: 21 October 2010 Patents Act 1977: Search Report under Section 17 Documents considered to be relevant: Category Relevant Identity of document and passage or figure of particular relevance to claims X 1-18 US 2004/0261790 Al (JOSHI ET AL.) See especially Figure 4 and paragraphs [0033]-[0034] X 15 FR2797189A1 (LENFANT) See especially the Figures and WPI Abstract Accession Number 2001-149850 [16] X 15 US 2009/0159719 Al (MILLET) See especially the Figures and paragraphs [0050]-[0052] X 15 US 2007/0247555 Al (DIERSING ET AL.) See especially paragraphs {0020]-[0032] X 15 FR2937884A1 (OSMOOZE) See especially Figure 1 and WPI Abstract Accession Number 2010-E87722 [32] Categories: X Document indicating lack of novelty or inventive A Document indicating technological background and/or state step of the art.Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of before the filing date of this invention.same category.& Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO & US patent docjments classified in the following areas of the UKCX Worldwide search of patent documents classified in the following areas of the IPC AO1M; A6IL; A61M The following online and other databases have been used in the preparation of this search report WPI, EPODOC Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk *.:r: INTELLECTUAL . ... PROPERTY OFFICE 15 International Classification: Subclass Subgroup Valid From A61L 0009/12 01/01/2006 AO1M 0001/20 01/01/2006 A61M 0011/00 01/01/2006 Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk